Screen pipe



Sept. 3o, 1941.

J. F. MALONEY SCREEN PIPE Filed Jan. 1l, 1940 soaoccoaodonclcauuPatented Sept. 30, 1941 UNITED sTATEs PATENT OFFICE SCREEN PIPE' Joe F.Maloney, Houston, Tex. Application Januar! 11, 1940, Serial No. 313,319

z calms (ci. iss-s) This invention relates to screen pipe for use inwells, and has for its particular object-the provision of a screen pipewhich will incorporate the various advantages of the use of gravel forscreening purposes.

Screen pipe generally consists of a metal pipe having openings cut orpierced therein at frequent intervals, so as to permit the inflow ofi'iuid through said openings while at the same time preventing theentrance of sand from the producing formation which would tend toclog upthe flow pipe and well.

In certain cases, after such a screen pipe has been set in position, abody of gravel has been placed within the well about .the outside of thepipe in order to stop or retard vthe entrance of sand and in order toprevent the packingof sand or other formation around the screen thusclosing the openings in the screen and preventing proper flowing of thewell.

It is an object of this invention to provide a screen pipe which willincorporate both the advantages of the metal pipe form of screen and theadvantages of the gravel screen. l

It is a further object of this invention to provide such aV device whichmay be made up in a factory or the like, transported to the ileld inunits of more or less conventional length with the gravel in placewithin each unit, and to join these units together easily and insubstantially conventional manner as the same are placed in the well.

Another object of this invention is to provide A a gravel screen pipewhich may be"easily and cheaply manufactured' and which will be ruggedin service and easy totransport and` use.

Other objects and, advantages will become apparent from the followingdescription taken in connection with the accompanying drawing, in which:

Fig. 1 is a side elevation with part broken away lsind shown in crosssection, illustrating a screen pipe constructed in accordance with thisinvention, with a set shoe threaded to the lower end thereof.

Fig 2 is an enlarged longitudinal cross section of the same structure.

Fig. 3 is a transverse cross section taken along the line 3 3 of Fig. 2.

With reference to Fig. l, it will be seen kthat the screen pipe of thisinvention is made up in sections designated generally by the numeral I,and may have connected to. its lower end any conventional set shoestructure such as generally impair the production of the projections Ilextending vradially. therefrom will,

indicated at yrand which ordinarily contains a back pressure valve Iwhich permits downow from within the screen but prevents upilow` intothe screen" through the bottom thereof.

Referring now to Figs. 2 and 3, each section of screen pipe consists ofan outer pipe 4 having perforations I therein, an inner pipe C havingslotted openings 1 therein, a spacing spider I interposed between thetwo pipes and secured in place by'a set screw l, a body of gravel Ilbetween the two pipes, and rings Il and i2 closing the ends of theannular space between the two pipes for the purpose ofl retaining graveltherein.

The outer pipe is preferably threaded internally at one end, as shown atIl, and externally at theother end, as shown at il, for connection with`adjacent annular sectionsy of the gravel screen pipe. The inner pipe ispreferably made slightly shorter than the outer pipe and is formed witha slight bevel Il and it on its exterior surface adjacent its oppositeends.

In assembling the -gravel screen pipe according to this invention, thering i2 may. first be secured within the outer pipe I by any suitablemeans, such as the screws l1 or the welding Il, or both. The spacingring I having Special then be secured on the inner pipe 1, and it willbe understood than any number of such rings may be employed as foundnecessary or desirable and positioned'wherever found desirable upon asingle length of inrier pipe. The inner pipe would then be insertedintoV the outer pipe from the end opposite the ring l2 until the taperedend I0 of the inner pipe fits within the opening through the ring i2,which lis-'pre ferably tapered and formed to provide a close fit betweenthese parts.

With the inner pipe in place within the outer pipe, lthe annular spacebetween the two will then be filled with the gravel l0, after which thering Il will be screwed into place within the outer of gravel screenpipe may be made up in a factory under supervision so as to provideassurance that all parts will be assembled in the proper manner, andthese sections of gravel screen pipe may then be transported as units tothe well and then joined together and joined to the other partscustomarily used with screen pipe, and inserted into the well.' It willbe seen `that the gravel screen pipe provided by this invention may beused in the same manner as any ordinary screen pipe and coupled anduncoupled with the same tools without danger of losing the gravel 5substantially closing the ends oi' the annular 15 space between vsaidpipes and retaining the gravel in place, the openings in said annularretaining diameter of the inner pipe and greater than th externaldiameter of the free tapered-ends of sai inner ypipe to receive onlythe' tapered end portions of said inner pipe and means for forcing oneof said rings toward the other whereby said inner pipe will be' grippedbetween said retaining rings being of a diameter less than the externxis ment.

rings and held in position against axial displace- 25 2. In a wellscreen. an outer perforated pipe, an inner perforated pipe having itsexterior surfaces tapered adiacent the ends of the inner pipe. a body ofgravel substantially lling the annular space between said pipes; anannular retaining ring substantially closing one end of the an.

nularl space between the pipes and having a tapered central opening toreceive the correspending tapered end of Ithe inner pipe, means forlining said retaining ring in the corresponding end of the outer pipe, asecond annular retaining ring substantially closing the other end 'ofsaid annular space, having a tapered central opening to receive thecorresponding end of the inner pipe, and cooperating screw threads 4onthe outer periphery of said second retaining r and on the interior ofthe outer pipe for axi y displacing said second retaining ring, uporotation. toward the rst recited ring to force .the tapered ends of theinner pipe into thev tapered openings of the retaining rings and gripsaid inner pipe tightly between, said retaining rings.

i JOE F. MALONEY.

